The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Internal combustion engines draw air into an intake manifold through an air intake. The air is mixed with fuel to form an air-and-fuel (A/F) mixture. The NF mixture is combusted within cylinders to drive pistons, which rotatably turn a crankshaft to produce drive torque.
In certain conditions, engine knock may occur. Engine knock corresponds to a vibration resulting from uncontrolled combustion in the cylinder chamber. Engine knock over a sustained period of time results in, for example, damage to pistons, cylinder rings, and/or exhaust valves. Engine knock also increases noise/vibration/harshness (NVH). An engine control systems may implement knock detection to detect, reduce and/or prevent engine knock, thereby improving engine performance and vehicle drivability.